A breast implant is commonly used to correct shape or volume deformity of the breast due to breast removal following cancer or to correct size and asymmetry. Examples of breast implants available in the United States include silicone gel-filled implants and saline-filled implants. However, silicone gel-filled implants and saline-filled implants diverge from an ideal implant.
Relative to saline implants, silicone gel-filled implants can offer superior feel; however, silicone gel implants have a higher capsular contracture rate and should be removed if ruptured. Further, a 1992 United States Food and Drug Administration (FDA) moratorium on the use of silicone gel-filled implants negatively impacted the perception of their safety. Restraints on approval of silicone gel implant devices and alternative implant filling materials still exist.
Saline-filled implants (also referred to herein as saline implants) have been FDA approved and have an excellent safety record spanning 30 years. On the other hand, saline-filled implants may feel less natural than silicone gel implants, and surface rippling can be problematic. If a saline-filled implant leaks, the subject's body absorbs the saline, and the volume of the saline-filled implant decreases. The amount of saline leakage can be substantial, sometimes to the point of being substantially free of saline. In this circumstance, the empty or nearly empty shell can be removed and replaced.
Additionally, physicians temporarily use a tissue expander to stretch or facilitate growth of tissue in a patient. For example, a surgeon may place a tissue expander in a mastectomy patient as part of reconstructive repair of the tissue. Tissue expanders commonly contain the same filling fluid and suffer similar physical problems as, e.g., saline-filled implants.
Due to regulatory overview by the FDA, introducing a breast implant or tissue expander in the United States can be fraught with enormous expense of time and money due to compliance with FDA requirements, which can involve extensive clinical trials and reporting occurring over the course of years. Typically, review of previously unapproved materials in, for example, breast implants or tissue expanders can be a leading factor in the regulatory approval delay for these devices.
Materials and implants that overcome the above issues would be well-received by those skilled in the art.